1. Field of the Invention
This invention relates generally to medical devices for human implantation during orthopedic surgical procedures and more particularly to medical staples and drivers for holding a medical staple during installation.
2. Prior Art
Medical staples are generally for use as attachment devices to maintain a ligament, or the like, onto a bone surface. To this end, the medical staple generally includes two or more legs that are usually straight and parallel, each having a point formed on a leg lower end with the other leg ends maintained to a web member that spans, at approximately a right angle between which legs, forming a U-shape. The staple legs are pointed to facilitate their being driven into a bone by application of a force to the staple web. Such force application is usually directed into the web by a driver that has one end fitted across the staple web with a force applied to the other driver end as with a hammer, or the like. Accordingly, a number of configurations of drivers have been developed for applying a force into a staple web, to urge the staple legs into a bone, with a ligament, or the like, maintained between which staple legs that is thereby clamped by the staple web against the bone surface.
An example of a driver that is positioned on a clamp type device for applying a driving force therethrough to urge spikes and pins of the clamp into a bone is shown in an earlier patent of one of the present inventors, U.S. Pat. No. 4,960,420. Additionally, a number of driver tools that involve opposing jaws have been developed for use with medical staples, where the jaws can either be closed against the staple web opposing sides, or are arranged to receive the staple web slid therebetween. Examples of such drivers are shown in U.S. Pat. No. 4,438,769; and in a 1992 Catalog of Linvatec, as part of a "Staple Fixation System". Examples of driver devices that provide for receiving a staple web between opposing jaws and that include arrangement for applying a clamping force to the opposite web sides, are shown in U.S. Pat. No. 4,263,903; U.S. Pat. No. D. 280,550; and U.S. Pat. No. 4,592,346. Also, for mounting an anchor type device to a driver end, a patent to one of the present inventors, U.S. Pat. No. 5,013,316, includes a threaded driver end for turning onto threaded post that extends axially from the top of the anchor head.
Similar to the driver of U.S. Pat. No. 5,013,316, the invention is a straight cylindrical driver that includes a threaded section on the driver end that is for turning into a threaded hole that has been formed through a web of a medical staple that the invention is preferably utilized with. Additionally, the driver of the invention provides a spring collet as the drive end adjacent to the driver threaded portion, for fitting into and maintaining a washer of the staple. The washer is fitted between to slide along the staple legs, and is to provide for clamping a ligament onto a bone surface wherein the staple is driven. Accordingly, the driver of the invention includes a combination of a spring collet end and threaded portion that are for mounting a staple and washer thereto. In which configuration, the driver is held by a surgeon during staple placement and is for use in driving the staple pointed ends into a bone. Which driver is distinct from the above cited patents and other devices within the knowledge of the inventors.